To promote the June 1 release of "Sisterhood of the Traveling Pants," a film about close friendships among teenage girls, Warner Bros. has launched two viral websites and has plans for extensive online media buys across sites such as MSN, MySpace, Alloy, Fandango and Latin music site Batanga, ClickZ reports. The primary site is heavily interactive, with components that can be customized and shared with friends, and viral marketer Electric Artists has launched www.friendshipquiz.net for users to create quizzes and send their friends to find out which among them know her best. Warner is promoting both sites through a network of college interns who post on message boards and send emails to friends.